The patent application EP 905464 A1 in the name of the same Applicant describes a plastic profile for refrigerator furniture units and the like provided with door and an inner door, having a bellows seal portion which forms a sealed closure between the door and the furniture, the profile and the seal portion being joined together or integral as a single piece produced by means of coextrusion of two materials having a different rigidity so as to allow, if necessary, easy separation of the seal portion from the profile along their joining zone, said profile having a groove able to receive a replacement bellows seal portion, said groove being defined by a pair of walls which extend vertically or obliquely from a base formed with a substantially C-shaped cross-section comprising two horizontal upper and lower sections, the latter being elastically splayable as a result of an elbow piece made of soft material and formed by means of coextrusion on the cross-section itself, this elbow piece therefore acting as a hinge so as to allow elastic splaying of said C-shaped cross-section, in particular of said lower section, so as to receive by means of snap-engagement the edge of said inner door inside the cross-section itself, and externally and underneath said C-shaped cross-section the profile forming a seal on the edge of said door.
For the purposes of installation, the profile with the coextruded seal is advantageously provided in the form of a rectangular frame welded at the corners and then assembled together with inner door and door, as is for example described also in the European patents Nos. 146,994 and 319,087 in the name of the same Applicant.
More particularly, according to the patent application EP 905464, the profile with the seal is welded so as to form a rectangular frame which may thus be mounted on an inner door of the same shape, generally with perimetral dimensions 0.5-3 mm smaller than the internal dimension delimited by the vertical section of the base of the profile. This assembly is made possible by means of shearing of the lower horizontal section of said base, performed automatically during extrusion (or by acting on the end part of the ready-cut portions) to a depth of 3-5 mm and over the whole of its extension, thereby making it possible to avoid welding in the corners of this section.
Each section therefore is excluded from welding and can therefore be splayed independently, by means of its hinging point, through angles even greater than 90xc2x0 so as to allow insertion of the inner door.
The operation of splaying of the abovementioned section may be generally performed manually by raising this lower section of all four sides of the frame through an angle sufficient for positioning of the inner door. Once this operation has been performed, the sections are released and the hinge brings them back by means of snap-engagement into their initial position, locking the inner door in the C-shaped cross-section of the base of the profile.
The profile and the inner door thus assembled are then placed on the door and the whole assembly is fixed by introducing foam into the cavity between door and inner door.
The profile, when it is inserted on the inner door, forms a single assembly therewith which must be moved, being able to withstand also in certain cases sudden stresses, without causing separation of the assembled parts.
This condition is very important when the two assembled parts are positioned on the foaming moulds, since rapid, precise and safe operation is possible only when it is ensured that said parts remain in a fixed position, without mutual displacement.
The present invention relates to a method, and the associated apparatus for implementing it, able to perform automated assembly of this kind of profile on the inner door of a refrigerator. More specifically, the present invention relates to a method for assembling in an automated manner on an inner door a profile (1) made of substantially rigid plastic, for refrigerator furniture units and the like provided with door and an inner door (31), having a seal which is made of substantially soft plastic and forms a sealed closure between the door and the furniture, the profile and the seal portion being joined together or integral as a single piece produced by means of coextrusion of two materials having a different rigidity, said profile having a base (3) formed with a substantially C-shaped cross-section defined by two substantially horizontal sections, i.e. an upper section (2) and lower section (4), and by a substantially vertical or oblique section (7), said cross-section being elastically splayable as a result of an elbow piece (8) made of soft material and formed by means of coextrusion on the cross-section itself, this elbow piece therefore acting as a hinge for allowing elastic splaying of said section (4) of said C-shaped cross-section so as to receive by means of snap-engagement the edge of said inner door (31) inside (19) the cross-section itself, characterized in that it comprises the stages of: a) providing said profile (1) in the form of a frame welded at the corners, b) stably resting said frame on a support (10), c) gripping said section (4) along all the sides of said frame using engaging means (12) so as to perform said elastic splaying, d) retaining said sections (4) in the splayed position, e) positioning said inner door (31) on said sections (2) of said profile base, f) releasing said sections so as to allow the elastic return of the profile base onto the edge of the inner door, g) extracting inner door and profile thus assembled from said support.
The invention also relates to an apparatus for performing said assembly method, comprising a support (10) for resting thereon said profile (1) in the form of a frame welded at the corners, and a device (11) comprising a first cylinder 17 supported by a rotatable platform 18 on which it is arranged horizontally and inside which there is a piston 19 which actuates a rod 20 which may impart a translatory movement to a second cylinder 15 which actuates an engaging means 12 translatable along its longitudinal axis as a result of sliding of an arm 13 which supports it, actuated by a piston contained inside the cylinder itself, said engaging means (12) being retractable.
So that characteristic features and advantages of the invention may be better understood, a non-limiting example of embodiment thereof is described below with reference to FIGS. 1 to 8 of the accompanying drawings. Said figures illustrate in a schematic manner a corresponding number of stages in the assembly sequence.